# Species Concepts (3)
Snow day guide: Write out the criteria for each concept, then write out one flaw
# Barriers to Mating
Snow day guide: This is an extension of the biological species concept. Focus on being able to recognize/write out scenarios that prevent mating from occurring (pre-zygotic = habitat, temporal, behavioral, and mechanical isolation)
#Allopatry vs Sympatry
Snow day guide: These are two ‘mechanisms’ by which species actually form (different from above). Be able to recognize/write out scenarios that would form new species for each